Barrier-to-autointegration factor 1 promotes gammaherpesvirus reactivation from latency

Gammaherpesviruses, including Kaposi sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV), are DNA viruses that are globally associated with human cancers and establish lifelong latency in the human population. Detection of gammaherpesviral infection by the cGAS-STING innate immune DNA-sensing pathway is critical for suppressing viral reactivation from latency, a process that promotes viral pathogenesis and transmission. We report that barrier-to-autointegration factor 1 (BAF)-mediated suppression of the cGAS-STING signaling pathway is necessary for reactivation of KSHV and EBV. We demonstrate a role for BAF in destabilizing cGAS expression and show that inhibiting BAF expression in latently infected, reactivating, or uninfected cells leads to increased type I interferon-mediated antiviral responses and decreased viral replication. Furthermore, BAF overexpression resulted in decreased cGAS expression at the protein level. These results establish BAF as a key regulator of the lifecycle of gammaherpesviruses and a potential target for treating viral infections and malignancies. Barrier-to-autointegration factor 1 (BAF) is a DNA binding protein involved in numerous pathways including transcriptional regulation, DNA damage response and nuclear assembly. Here, Broussard and colleagues characterise its role in gammaherpesvirus reactivation.

Automated summary

This study reveals that the barrier-to-autointegration factor 1 (BAF) is necessary for the reactivation of Kaposi sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) by suppressing the cGAS-STING signaling pathway. BAF destabilizes cGAS expression, leading to increased antiviral responses and decreased viral replication. BAF could be a potential target for treating viral infections and malignancies.